Longcroft, who lives in Scotland, is still waiting for patents and started crowdfunding for the bottle on Monday. He has set a goal of R430,000 (£25,000), of which he has raised about R140,000 (£8,000) so far.

He hopes to see the bottles available in stores by the end of the year, and that they will be sold for about R14.51 (85p) and R15.36 (90p) so that they become a viable alternative to plastic, according to The Times.

Business Insider asked Choose Water to test one of the water bottles, but they said no because they don't want anyone to be left alone with the bottle in case they steal its secrets.